She told her family: "On my approach to the pole I was in low cloud and the sastrugi ice was extremely heavy, making pulling the sledge very difficult. I kept telling myself, surely this couldn't go on for ever?

"Suddenly, with a mile to go to the American base, the sun came out and I was able to touch the pole at the end in glorious sunshine."

Mrs Thornewill beat her rival, Rosie Stancer, 43, of Barnes, south-west London, who was said to be just a few days behind.